After more than a year of investigations, Israeli police said they have found evidence that Prime Minister Benjamin Netanyahu took bribes. Picture: Ronen Zvulun, Pool via AP

Tel Aviv - After more than a year of investigations, Israeli police said Tuesday they have found evidence that Prime Minister Benjamin Netanyahu took bribes, in an announcement that could send shock waves through the country's political system.

Police said they found an "evidentiary basis" for bribery fraud and breach of trust.

From 2007 to 2016, Netanyahu - along with his wife, Sara, and son, Yair - allegedly accepted around 1 million shekels' (R3.3 million) worth of cigars and jewellery from Israeli Hollywood producer Arnon Milchan and Australian billionaire James Packer, in a manner that constituted a bribe from Milchan and a breach of trust regarding Packer, according to police.

"The relationship between the prime minister to Mr Milchan was a system of bribery relations that amounted to a criminal offence and not innocent relations between friends," police stated.

In a separate case, police allege that Netanyahu accepted a bribe from Noni Mozes, who publishes the Israeli newspaper Yedioth Aharonot. Netanyahu moved to weaken competing newspaper Israel Hayom with legislation and other means for Mozes' benefit, police allege.

The announcement - widely seen as a recommendation to indict the premier - will roil Netanayahu's conservative governing coalition and increase calls by critics for him to resign. However, he maintains a strong base of support and is not required to step down.

Israel's attorney general will make the final decision on whether to press charges against the kingpin of Israeli politics.

Netanyahu, in a live televised speech, denounced the recommendations, saying that he would continue to lead the country. He said this will "end in nothing."

"They have brutally attacked my wife and children to hurt me," he said.

Among police suspicions are that Netanyahu worked with Milchan, a well-known Hollywood producer, to arrange a US visa, lessen the billionare's tax burden, and assist with business ventures.

The investigation into Netanyahu's relationship with Mozes are based on recordings obtained from the premier's former chief of staff, Ari Harow, that allegedly show the prime minister and publisher "bartering" to further their personal interests.

Police said that an evidentiary basis had been formed against Milchan and Mozes for giving bribes.

Netanyahu has been questioned in the probes multiple times, which have also ensnared his closest confidants and made for lurid headlines detailing alleged gifts of pink champagne and cigars from billionaires Milchan and Packer.

Some lawmakers in the premier's conservative Likud party have said Netanyahu should not resign even if indicted.

Meanwhile, tens of thousands of Israelis have taken to the streets in recent months calling for Netanyahu's resignation.

Netanyahu has previously accused the media of orchestrating a "witch hunt" to overthrow the most conservative governing coalition in Israel's history.

In 2008, then Israeli prime minister Ehud Olmert resigned due to corruption allegations.